The EIT tables were output incomplete as the
first sections were always dropped.

(2 sections, last_section == 1)
Ex: section 1
    section 0
    secton  1

IsCompleteEIT is always true in first condition in that case.
It is also always true if section is N/N.
first_section > -1 && section_number == last_section because
it has just been added.

Doing the check before effectively adding the section
allows a correct evaluation against current section.
Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>